This variable contains the date when the individual first began receiving widowed
spouse benefits and is stored as a SAS date variable. Benefits always begin on the
first day of the month. Individuals were eligible to receive their first payment in
the month they turned 60 unless their birthday was the first day of the month, in
which case they were eligible for their first payment the month before they turned
60. Individuals born on January 1 were eligible to receive their first payment in
the December before they turned 60.Start dates range from January 1962 to December
2012.